The Shake Shack 'Shroom Burger

June 22, 2023
9 Ratings
Photo by Bobbi Lin
  • Prep time 30 minutes
  • Cook time 1 hour
  • Makes 4
Author Notes

My childhood was fueled by Dr. Praeger's Purely Sensible Foods' frozen veggie burgers—thin discs with real vegetable pieces (hey, is that a corn kernel?) that I would eat, alongside the rest of meal, with a fork and knife.

I enjoyed (even loved) Dr. Praeger's, but I did not think of them as burgers at all—neither "juicy" nor "satisfying," neither a treat to look forward to nor a complete meal. A Dr. Praeger's patty would have been eclipsed by a bun on either side and never posed a fair match to a meat burger. They were, as named, "purely sensible."

It wasn't until I tried the Shake Shack 'Shroom Burger that I realized veggie burgers needn't be sensible. Why coax vegetables (and, for most recipes, grains and binders and starches, too) into the shape of a patty? Vegetarian burgers can be entirely nonsensical and untraditional and just as messily delicious as any meat burger on the menu.

The 'Shroom Burger forgoes the constraints of the patty form to present a mushroom in its most dignified state—breaded, fried, and full of cheese. It's insanity! When you eat the sandwich, you work your way through the roasted mushroom barrier to hit the cheese geyser at its center. (Geyser is not an exaggeration: When you receive your 'Shroom Burger at the restaurant, you should let the burger cool for a few minutes, lest you risk a cheese eruption.)

Whenever I've ordered a Shroom Burger—which, not to get too emotional over a sandwich or anything, but these have been my hungriest, grumpiest, and most celebratory moments (3 p.m. after turning in my last college final; 10 p.m. after moving a 200-pound dresser into a fifth-floor walk-up)—the how of the matter has become a subject of conversation. Just how do they get the cheese in there? Is it with a giant syringe? A peculiarly hollow mushroom? An elaborate song and dance?

It turns out that you don't need to purchase a specialty cheese syringe (oh yes, these exist). The recipe, which is published in the book Shake Shack: Recipes & Stories is fairly simple to make at home, if you don't mind a bit of deep frying.

Simply roast the mushrooms, slice them in half through their bellies, then hide a ball of the filling—a mixture of grated cheese, onion, garlic, flour, egg yolk, and cayenne pepper—in between the top and bottom. Coat the reconfigured mushrooms in flour, beaten eggs, and panko breadcrumbs, then get them into the hot oil.

The panko will crisp, the cheese will melt, and you'll have a vegetable burger that can hold its own snuggled up next to a slice of tomato and between two buns. All you need now is a cold milkshake.

Reprinted from Shake Shack. Copyright © 2017 by Shake Shack Enterprises, LLC. Published by Clarkson Potter/Publishers, an imprint of Penguin Random House, LLC. —Sarah Jampel

Test Kitchen Notes

The 'Shroom Burger is the ultimate example that veggie burgers don't need to be just ground vegetables and grains. Nestled between a tender, sliced portobello mushroom cap is a glorious core of melty cheddar and muenster cheeses which seamlessly blends with the creamy, tangy ShackSauce smothered onto the soft potato buns. —Food52

What You'll Need
Watch This Recipe
The Shake Shack 'Shroom Burger
  • For the mushroom caps & filling:
  • 4 4-inch-wide portobello mushroom caps
  • 1/4 cup canola oil, plus more for deep-frying
  • 1/2 teaspoon kosher salt
  • 1/8 teaspoon freshly ground black pepper
  • 1 1/2 cups plus ¼ teaspoon flour, divided
  • 3 eggs plus 1 egg yolk, divided
  • 2 cups panko breadcrumbs
  • 1 1/2 cups grated muenster cheese
  • 1/2 cup grated cheddar cheese
  • 1/2 teaspoon white onion, minced
  • 1/8 teaspoon garlic, minced (about ¼ clove)
  • 1 pinch kosher salt
  • 4 tablespoons ShackSauce
  • 4 hamburger potato buns, toasted
  • 4 leaves green leaf lettuce
  • 8 ¼-inch-thick slices ripe plum tomatoes
  • For the ShackSauce:
  • 1/2 cup mayonnaise
  • 1 tablespoon Dijon mustard
  • 3/4 teaspoon ketchup
  • 1/4 teaspoon kosher dill pickling brine
  • 1 pinch ground cayenne pepper
  1. For the mushroom caps & filling:
  2. Roast the mushroom caps: Heat the oven to 375° F. Put mushroom caps on a medium baking pan. Rub caps all over with ¼ cup of canola oil, then season both sides with the salt and pepper. Arrange mushrooms, gill side down, in a single layer and roast until tender, 30 to 35 minutes. Remove from the oven and set aside to cool. Once cool, slice mushrooms in half horizontally (through their bellies, like you're slicing a hamburger bun).
  3. Put the 1 ½ cups flour in a wide dish, beat 3 eggs in a separate wide dish, and put the panko in a third wide dish. Set aside.
  4. Make the filling: Mix together the cheeses, onion, garlic, remaining ¼ teaspoon flour, remaining egg yolk, and cayenne pepper in a medium mixing bowl. Set aside.
  5. Shape the filling into 4 equal disks, ½-inch smaller in diameter than the mushroom caps. Place cheese disks on gill side of each mushroom cap, cover with other half of cap, cut side down, and gently press together to secure the filling.
  6. Dredge the stuffed mushroom caps in the flour, then dip in the beaten egg, coating them completely, then dredge in the panko. Set prepared mushrooms on a plate and refrigerate while heating the oil to deep-fry them.
  7. Cook the mushroom burgers: Pour the oil into a deep, wide pot to a depth of 3 inches. Heat over medium heat until the oil reaches a temperature of 350°F on a candy thermometer. Deep-fry the prepared mushrooms, one or two at a time, until golden brown and crisp all over, about 3 or 4 minutes. Transfer mushrooms with a slotted spoon to drain on paper towels. Immediately season with salt.
  8. Spoon the ShackSauce onto the top bun. Add 1 leaf of lettuce and 2 slices of tomato. Transfer the mushroom burgers to the prepared buns. Enjoy!
  1. For the ShackSauce:
  2. Whisk together all ingredients to combine. Refrigerate any extra for up to one week in an airtight container.

See what other Food52ers are saying.

  • Nicole Adman
    Nicole Adman
  • Ellis D Padilla
    Ellis D Padilla
  • louisez
  • Teresa Gonzalez
    Teresa Gonzalez
  • Uyen Nguyen
    Uyen Nguyen

14 Reviews

andrea S. August 13, 2023
I made these with a few tweaks based on comments (thank you!) and they turned out well. I used 6" portobellos and cut them in half before roasting, and roasted the halves cut side together. I stirred up the cheese mixture (ground onion powder not fresh), formed into patties with the fork and refrigerated them. After assembly and dredging, I put them in the fridge for ~30 mins. I cooked them in our mini fryer which kept the temp at 350 degrees and nearly all the oil was left afterwards. Because the cutting in half is kinda challenging, I really thought the cheese was going to spill out in the fryer, but nope. They all stayed together & fried crisp with no leakage. The shake sauce needs a bit more zip, but otherwise we all agreed we enjoyed them for a Saturday night dinner. I think the fryer really helped cook them through while maintaining the coating, and kept them from being greasy.
Cindy July 6, 2023
I made this for dinner last night. I did take advice and cut the mushroom caps before cooking. Great Tip!! These were extremely YUMMY! Thanks for the great recipe.
TeenCook March 31, 2023
This is an awesome recipe! I cooked these for my family and they were amazing!
Steve September 21, 2020
These are awesome! I think the issue some cooks are having has to do with how thick the caps are. No 2 portabellos are going to be the same. Even if you do the double cap burger they come out great.
Nicole A. July 25, 2020
Agree with Allan, you should cut the caps before roasting because they're too flimsy afterwards, which leaves room for error. Just cut the cap before, and roast as you would normally with the top slice still on top of its lower half. These were a little nerve-wracking to make, and not as mindlessly easy as it appears in the video, but ultimately delicious and crispier than what I get in Shake Shack. I used a gluten-free flour blend (Bob's Red Mill garbanzo bean blend, to be specific) and gluten-free panko (Ian's, to be specific) and it was perfectly crisp.
Allan November 24, 2019
When I roast these, as the recipe asks for, the mushrooms flatten and there isn't anyway for me to cut them as the recipe calls for. The first time I made them I ended up using two mushrooms for each burger and putting the cheese in the middle. Tonight I'm just stuffing the gills and hoping for the best. Any suggestions?
Ellis D. August 8, 2018
I absolutely loved it. I just wanted to say that some mushrooms will not be able to cut the cap. If you refrigerate the cheese mix (cheesy goodness) it will not crumble nor make a mess. I will try to bake it next time, bc it's too oily .
louisez February 18, 2018
Big oops. What I meant to ask if these can be baked. Sorry for the typo. Want to make these for someone for whom oil/frying is a problem. Thanks!
Teresa G. February 20, 2018
I have both baked and air-fried these for a healthier option and they tasted great! My three boys ate them up and asked for more!
Uyen N. August 22, 2019
How long did you bake them for and at what temp?
louisez January 17, 2018
Can these be naked instead of fried?
Keith January 10, 2018
Remove the gills from the caps, or no? My first attempt was with gills removed and the caps shriveled so much during roasting I couldn't slice them. Ended up combining 2 caps with filling in between.
Ellis D. August 8, 2018
I only removed the stem not the gills. And I saved the juices for next soup or rice.
Teresa G. June 26, 2017
Made this for my family tonight and even our young sons tore them up! We love anything Shake Shack, but these were a definite hit! Thanks! :)